Web services

Hi Jerome,

I am interested in working with the web services and particularly with the amf support in Moodle 2. I have some questions :

• In order to try it out I'm guessing I can use some of the test clients in contrib/patches/dfws/client/ with the web service servers in Moodle HEAD??
  
• Is the stuff in the contrib/patches/dfws/webservices all integrated into Moodle HEAD?
• I can't see any test Flash client there, is there a client available to test the web services using amf?

Thanks for your time and this exciting contribution to Moodle!

Jamie

Hi Jerome,

Found that the following patch was needed in order to get the amf server to return error messages to the client :

Index: webservice/amf/lib.php

===================================================================

RCS file: /cvsroot/moodle/moodle/webservice/amf/lib.php,v

retrieving revision 1.3

diff -u -r1.3 lib.php

--- webservice/amf/lib.php 12 Mar 2009 09:03:47 -0000 1.3

+++ webservice/amf/lib.php 21 Mar 2009 08:22:55 -0000

@@ -54,6 +54,7 @@

 /// run the Zend AMF server

 $server = new Zend_Amf_Server();

+ $server->setProduction(false);

 $server->setClass($classpath."_external");

 $response = $server->handle();

 echo $response;

Wonder if we could include a switch so that we could turn the debug output on or off to the admin interface? Would other servers need this functionality as well? Servers could be off, on with debug messages returned to client or on in production mode.

Jamie

I committed a test client for batch operations exposed by user/external.php

You can try it out by checking out the latest version of Moodle HEAD and going to {rooturl}/webservice/amf/testclient/

Hey Jerome

I had to implement AMF for a project here... it's on top of 1.9 of course, but it uses Zend AMF.

Anyway, I wrote a small Introspection class, that reads in from $CFG a list of directories that have AMF blessed service files in them.

Each class that wants its methods exposed as AMF services must implement a simple Interface (no contract methods, just so the Introspection stuff can differentiate which ones to use).

For each of the services it finds, it uses php5's Reflection stuff to find the public methods and their arguments, and returns them.

Then, my awesome colleague Jordi wrote a flash client (which he's releasing under the WTFPL) which connects to local/amf/server.php and by default calls the getMethods method on the Introspection class, and then offers an interface to make simple method calls and prints the result.

You can check this out here:

http://git.penny.liip.ch/?p=moodle.git;a=tree;f=local/amf;hb=refs/heads/mdl19-common

which wants to go inside local/ in a normal moodle 1.9 checkout.

At the moment I am using this successfully to connect to a custom build question type that just records scores and state from a flash game.

Since the flash client runs in the browser, when it makes AMF connections, it sends the same cookies as the normal request, so it runs as the logged in user.

You could use it to test some of the Moodle 2.0 stuff you're doing, except that it must use class methods of course, you can't use it to test functions (but you're free to modify it of course). You just have to:

make a amfservices/ directory somewhere and set $CFG->amf_servicepaths (this can be an array)

Eg: mine looks like:

$CFG->amf_introspection = true;
$CFG->amf_servicepaths = $CFG->dirroot . '/question/type/externalflash/services/';

make a file in that directory and create a new class


class something implements AmfService {
public method someService() {
}
public method someotherService($foo, $bar) {
}
}

The only gotchas are that class state doesn't really get kept, and constructors can't take arguments.... essentially method calls are treated like static - so make sure they take all the arguments they need and don't expect state to be kept between calls.